Facial paralysis reconstruction

Our faces serve critical physical, emotional, social and psychological functions and facial paralysis may adversely affect all these functions.  Important physical functions include the ability to blink for eye protection, lower eyelid support to permit eyelid closure, nasal support to maintain nostril opening, and muscle support in the upper and lower lips to prevent mouth drooping and drooling.  Furthermore, a unique function of the face is its ability to express socially appropriate emotions and animations which include smiling and natural movement with speech.  Individuals with facial paralysis hence experience significant functional and aesthetic disruption that adversely affects their physical, social and emotional well-being.  Reconstruction of facial paralyis often brings great satisfaction to affected individuals.

Anatomy of the facial nerve

The facial nerve is an important and anatomically complex nerve that controls the majority of the animations of the face.  It consists of an upper and lower trunk, which divide into five main branches: the temporal, zygomatic, buccal, marginal mandibular and cervical.  There are interconnections between some of these branches and there is also significant variation between individuals.

How does it manifest?

The extent and degree of facial nerve paralysis depends on the affected branches or trunks.

  • The temporal branch chiefly innervates the frontalis muscle and is responsible for raising the eyebrow. Facial paralysis involving the temporal branch thus causes brow drooping.
  • The zygomatic branch animates a portion of the muscle around the eye involved with blinking, forceful eye closure and lower eyelid support. Loss of zygomatic branch function results in difficulty with or incomplete eye closure (lagophthaloms), and drooping or outward rotation (ectropion) of the lower eyelid.  The zygomatic branch also supplies the muscles involved in smiling and elevating the mouth corner and paralysis also results in droop of the latter.  This may result in involuntary drooling as well as speech difficulties.
  • The buccal branch supplies some of the cheek muscles involved in keeping the cheek skin taut and is important in chewing, whistling and smiling.
  • The marginal mandibular nerve aminates some of the lip depressor muscles and paralysis results in an abnormally high lower lip and asymmetrical smile.
  • The cervical nerve branch supplies the some of the neck muscles and maintains its muscle tone.

How does it arise?

There are a multitude of causes of facial nerve paralysis.  These include:

  • Tumors affecting the nerve itself or arising in the nearby salivary glands. Resection of the tumors sometimes requires intentional sacrifice of the nerve.
  • Bell’s palsy. This is the most common cause of acute facial nerve paralysis and has no known cause.  Individuals experience partial recovery over a few months but some have residual facial weakness.
  • Traumatic injury.  This may involve crush injuries or nerve transections from accidents or interpersonal violence.

Facial paralysis reconstruction: giving life to the face

Reconstruction of the paralyzed face is extremely important in the functional and psychological rehabilitation of the individual.  The type of reconstruction performed is dependent on the cause of the facial paralysis, the duration of paralysis, the individual’s age and wishes.  Successful reconstruction restores quality of life significantly and improves social and societal reintegration.  Facial reanimation requires an individualized approach, accurate assessment, precise technical execution and an experienced practitioner.

Acute facial nerve paralysis Treatment

Eye protection measures are required to preserve the lubrication of the eye and prevent formation of corneal ulcers due to desiccation (dryness), which may lead to visual loss.  This may include nighttime eyelid taping, use of lubricant gels and moisture chambers.  Severe cases may require minor surgery to suture the eyelids partially together.

Acute facial nerve paralysis caused by tumor resection or transection of the nerve is ideally repaired immediately in the operating room using microsurgical technique.  This involves joining the ends of the cut nerve using ultra-fine sutures that are thinner than a strand of hair.  In cases where there is a loss of a length of the nerve, nerve grafts may be harvested from the inner forearm or the calf to bridge the nerve defect.

Chronic facial nerve paralysis treatment

Reconstruction of chronic facial paralysis is dependent on the individual’s wishes for static and/or dynamic symmetry.  Procedures that are often used to restore static symmetry include:

  • Browlift in the upper face
  • Eyelid repositioning and/or tightening surgery in the lower eyelid
  • Facelift in the mid and lower face
  • Suspension surgeries involving the use of tendons to open the nostril and elevate the mouth corner
  • Neck lift

Procedures that are often used to restore dynamic symmetry and movement of the face include:

  • Distant flap transfer using muscle and nerves from the chest, abdomen or thigh <clickable link to “Reconstructive Services, Reconstruction of the Head and Neck, Treatment, Distant Flaps>
  • Use of intact adjacent nerves to innervate the facial muscles, including the nerve supplying tongue movement or the nerve supplying the chewing muscles
  • Use of the intact facial nerve from the unaffected side of the face to innervate the facial muscles through use of a nerve graft

The Picasso Advantage

The head and neck region is a complex and intricate one that serves critical physical, emotional, social and psychological functions.  Reconstruction of this region requires restoration of both function and aesthetic and necessitates experienced and skilled practitioners.  Dr Yeo has a keen clinical interest in this area and has been at the forefront of delivery of this care.  He received postgraduate training as an international fellow under the illustrious Professor Hung-Chi Chen, one of the global leaders in advanced reconstructive microsurgery in the head and neck.  Dr Chen is also one of the global authorities in intestinal flap reconstruction of the head and neck region and Dr Yeo is pleased to have the unique distinction of performing intestinal flap reconstruction of the pharynx in Singapore.